The safety helmet has the effect of protection the head of the driver so as to prevent from accidents. In many nations, it is required to wear the safety helmet in driving base on the traffic rules.
With the progress in technology, not only having the function of protection, the safety helmet also provides the function of air conditions so that the driver will feel comfortable.
However at night, the drivers at the rear side are not easy to adjudge whether a driver is at the front side so that accidents occur.